Method of cleaning carbon and combustion deposits from spark plugs



Feb. 8, 1966 E. OLSON 3,234,047 I METHOD 0 L CARBON AND COMBUSTION D 5FROM SPARK PLUGS Filed Feb. 5, 1962 f A @llla 1 IIII I I g II IuvnrroRATTORNEY United States Patent Oiiice EZBQM? Patented Feb. 8, 19663,234,047 METHOD OF CLEANING CARBON AND COMBUS- TION DEPOSITS FROM SPARKPLUGS Everette C. Olson, 1482 College Hill Drive, Columbus 21, OhioFiled Feb. 5, 1962, Ser. No. 171,172 4 Claims. (Cl. 134--2tl) Thisinvention relates in general to cleaning devices and particularly to themethod and apparatus for cleaning foreign deposits on metallic objects.

The present invention is of particular interest and finds unique utilityin the cleaning of carbon and chamber combustion deposits from sparkplugs. It is to be understood, however, the invention is not limited tospecific workpiece or object to be cleaned and the deposits may havebeen made or produced naturally, accidentally, or intentionally. Theword cleaning as used hereinafter is defined, therefore, as the act ofremoving adhering matter from an object without particular regard to thenature of the matter or the composition of the object. This will includethe removal of dirt, scale, rust, oxides and deposits formed duringchemical or physico-chemical actions.

The principal prior art method of cleaning spark plugs is by the sandblast method. The cleaning action is limited to brute force and in manyrespects the spark plug is in a worse condition after it is purportedlycleaned than before. The sand blast will not remove carbon formed inpits, clefts and crevices. Further, the sand deposits left on the plugmay be as bad as the original carbon. Finally, the spark plug may bephysically injured if the blast is not properly controlled, thereby, thesand blast method is limited to cleaning of the meta-l since theporcelain would easily be damaged.

In other prior systems for the cleaning of deposits from objects otherthan spark plugs there is the caustic or acid bath. More recently themore sophisticated systems include an ultrasonic generator to speed upthe cleaning action. To enhance the utility of the ultrasonic devices,combination systems, including pressure and container arrangements, havebeen proposed. The ultrasonic systems, because of the size of theobjects and the nature of the deposits, are not completely effective tothe cleaning of many types of foreign deposits.

The present invention provides a new and improved cleaning method thatfinds special utility in the cleaning of gasoline combustion chamberdeposits from the spark plug. More specifically, the invention generallycornprises immersing the spark plug or object in a caustic bath, andapplying an electrical current to the bath to impart a pulsating motionto the liquid. Also, the liquid becomes heated in the transformation andcirculation. The pulsating movement of the heated liquid through andaround the object to be cleaned is extremely effective in removing allthe foreign deposits from the entire surface of the object.

Accordingly, it is a principal object of the present invention toprovide a new and improved cleansing device for the removal of foreignmatter from a workpiece.

It is another object of the present invention toprovide a new andimproved cleansing device that completely cleans the workpiece withoutdamage thereto.

Another object of the present invention is to provide a new and improvedcleansing device that employs a liquid bath having a pulsatingcirculatory motion imparted thereto.

Another object of the present invention is to provide a new and improvedcleansing device that employs a liquid bath that is heated to enhancethe cleaning action.

Still another object of the present invention is to provide a new andimproved cleansing device that is relatively simple in operation anddoes not require trained or skilled operators.

Finally, another object of the present invention is to provide a new andimproved cleansing device that is comparatively inexpensive tomanufacture and utilize-s mostly conventional components.

Other objects and features of the present invention will become apparentfrom the following detailed description when taken in conjunction withthe single figure drawing showing a preferred embodiment of theinvention.

Referring to the drawing, there is illustrated a preferred embodiment ofthe present invention generally comprising a container 20 having a fixedsupport 22. This support further includes a combustion chamber 30 and areceptacle 34 therein for receiving the workpiece or object to becleaned. Also within the container 29 is a caustic fluid 11 that iscirculated through the combustion chamber 30, around the object ltl andthen recycled. To cause the continuous circulatory movement of the fluida means 455 is provided for interjecting an electrical current to thefluid in the chamber. This current, through violent chemical action,causes a pulsating wave to be imparted to the caustic fluid togetherwith a heating action.

The pulsating and heating action on the fluid causes the fluid tocirculate in a continuous motion around the object Ill to be cleaned. Inthis way the entire object 10 is cleanedand if object 10 is a sparkplug, the porcelain as well as the points will be cleaned. No damage tothe object occurs and no foreign material is substituted for thatremoved.

Referring specifically to the drawing, container 20 may be of thepolyethylene plastic or other plastic material; alternatively, container26 may be of glass or of asphalt base. Within the container 20 is acaustic fluid, such as potassium hydroxide or sodium hydroxide, in aconcentrated saturated alkaline solution. Within the container 20 andimmersed in the caustic solution is the support piece 22. This supportpiece is preferably of ceramic but may be rubber or other material. Inthe upper portion of the support 22 there is a receptacle 34- forholding the object to be cleaned in the caustic solution. The size andshape of the receptacle is of course dependent upon the size, shape andnumber of objects to be cleaned at any given time. In the preferredembodiment of the figure a spark plug 10 is shown as the object to becleaned. The receptacle 34 is therefore made of a general shape tosupport in an upright position the plug it).

In the lowermost portion of the support 22 there is a combustion chamber30. In this particular embodiment chamber 30 is elongated, i.e., havinga greater diameter in its length than in its width. Communicationbetween the chamber 30 and the receptacle 34 is maintained by theinjection orifice 4. ther than the injection orifice 4, the chamber 3%has its ends sealed off. Also entering the chamber from a somewhatcentral area are fluid circulating tubes 35 and 36. It is understood, ofcourse, the number, size, and position of these tubes may be a matter ofchoice so long as they provide sufiicient recirculation of the fluid.Finally, at the lower end of the container 2% there is provided anorifice in intimate relation with the chamber 30. A seal or grommet 33prevents the loss of fluid from the chamber. Entering the chamber 30through the grommet 33 are a pair of electrodes 2a and 3a having theirone end connected to power supply 40. In this embodiment the powersupply simply comprises a voltage source 5, a dropping resistor 6, andan on-oif switch 1. The other ends of the electrodes 2a and 3a arepermitted to end freely within the chamber.

In the construction of the embodiment shown in the figure a wire havinga standard number 18 gauge was 3 utilized as the electrodes 2a and 3a.Again these electrodes may comprise other sizes of wire either strandedor solid; or alternatively, the electrodes may be formed as part of thechamber 30. The electrodes 2a and 3a are conventionally covered withvinyl plastic and are of different lengths, the electrodes 2a having agreater length than that of 3a. The end 2b of electrode 2a and end 3b ofelectrode 3a are skinned back to allow an exposed area of the electrodeswithin the chamber 30. The position of the wires and particularly theposition of the one exposed end to the other exposed end was found to besomewhat critical and must be corrected for uniform circulatory actionas explained hereinafter. In this particular embodiment the one exposedend was approximately four inches from the other exposed end.

In operation of the cleansing device shown in the figure when theswitch1 is closed,-a nonlinear electrical field is created at the exposedareas 2a and 3a of the two electrodes 2b and 3b. This electrical fieldcauses a combustion in the caustic fluid surrounding the exposed areas2a; The combustion in turn causes the fluid around I the exposed areasto sputter and to become violently heat- I and 3a.

ed. When the fluid in this localized area arrives at a state wherecombustion can no longer occur, the combustible components in the fluidare consumed and the combustion ceases. The combustion, however, at thisstage will have caused the fluid to become agitated and heated givingrise to a thermal current. This current in turn washes away thenon-combustible fluid and introduces, through the closed fluid-loop,cool caustic fluid. With the new fluid now surrounding the exposedareas, com-v bustion again occurs. Thiscycle of combustion andnoncombustion occurs repetitively thereby imparting a pulsating actionto the fluid.

The caustic fluid being subjected to pulsating agitation in thecombustion chamber is forced up through the injection orifice 4 into theobject receptacle 34 over the walls 22a and 2211 down the walls of thecontainer and then back into the combustion chamber 30 through tubes35.and 36. The pulsating heated caustic fluid passes through thereceptacle 34 and consequently forces its wayinto the pits, crevices andall areas small or large .of the object 10 that may contain foreignmatter that is desired to be removed. To assure circulatory movement ofthe fluid 11 in the direction toward the object 10, the orifice 4 is ofgreater diameter than the return orifices 35; Alternatively, it may bedesired under certain.

and 36. conditions to incorporate a check valve to assure the movementof the fluid 11 in the proper direction.

The time required to cleanv the object .is of course dependent. upon:the object and the accumulation of In the cleaning, of a single sparkplug,

It] may be desired in certain instances to include a circulating waterbath for removal of the;caustic fromthe object foreign deposits. it wasfound tobeof the order of 3 to5 minutes.

and to rinse the object for handling.

Although there is described certain and specific .illustrations of theinvention','deparu1resmay be had thereto without departing from itstrue. spirit and scope.

What isiclaimed is:

1. The method of cleaning carbon and combustion .deposits from sparkplugs comprising the steps-of immersing the sparkplug in acaustic ,fluidbath, supporting said plug in an upright position'in said bath,confininga portion of'said fluid to a given area in contiguous relation to saidsupported sparkiplug, applyingan electrical voltage to said fluid'insaid given area to cause combustion therein andthereby impart apulsating motion thereto and to heat the same, restricting the movementof said pulsating fluid to leave said given area in one direction and toforce the heated caustic fluid into a continuous circulatory movementpast said spark plug, and'replenishing said fluid in said confined areawith fresh fluid from :said bath.

2.;Themethod as set, forth in claim 1 wherein ;said caustic fluid ispotassium hydroxide- 3. The method as set, forth in .claiml wherein saidcaustic fluid issodium hydroxide.

4.:The-method as set forth in claim 1 wherein said caustic fluid is aconcentrated alkaline solution.-

Reterences Cited by theExaminer. 1,

UNITED STATES PATENTS 1,403,686 1/1922, Heller. ,313--127 1,913,442 6/1933 Hanks 2 19288 1,992,309 2/1935; Hultman- 204 -274 2,307,928 1/1943Hogaboom; 204.141 2,346,562: 4/1944 De Long 204-141 2,470,741 5/1949Gordon 204-273 2,582,781 1/1952 Johnson 219-288 X 2,807,701 9/1957Conlinzet al.. 2l9-288 2,836,700 5/1958 Chapman 21940.6 2,888,9391 6/1959 Nitsche ,204281 JOHN'H. MACK, Primary Examiner.

JOHN R.- SPECK, Examiner. R. GOOCH, Assistant Examinerp

1. THE METHOD OF CLEANING CARBON AND COMUBSTION DEPOSITS FROM SPARKPLUGS COMPRISING THE STEPS OF IMMERSING THE SPARK PLUG IN A CAUSTICFLUID BATH, SUPPORTING SIAD PLUG IN AN UPRIGHT POSITION IN SAID BATH,CONFINING A PORTION OF SAID FLUID TO A GIVEN AREA IN CONTIGUOUS RELATIONTO SAID SUPPORTED SPARK PLUG, APPLYING AN ELECTRICAL VOLTAGE TO SAIDFLUID IN SAID GIVEN AREA TO CAUSE COMBUSTION THEREIN AND THEREBY IMPARTA PULSATING MOTION THERETO AND TO HEAT THE SAME, RESTRICTING THEMOVEMENT OF SAID PULSATING FLUID TO LEAVE SAID GIVEN AREA IN ONEDIRECTION AND TO FORCE THE HEATED CAUSTIC FLUID INTO A CONTINUSOUSCIRCULATORY MOVEMENT PAST SAID SPARK PLUG, AND REPLENISHING SAID FLUIDIN SAID CONFINED AREA WITH FRESH FLUID FROM SAID BATH.